Cross Reference to Related Application
This application is similar in some aspects to U.S. Ser. No. 741,831 filed concurrently which shares a common assignee.
1. Field of the Invention
This invention relates to the subject of supported metal skeletal or porous catalysts. Methods of changing the form and structure (i.e., surface area, particle shape, pore structure, surface and bulk composition) which control the ultimate performance of a skeletal type catalyst comprises the subject of the invention. This invention includes fabrication techniques and the resultant supported skeletal catalyst.
2. Description of the Prior Art
The skeletal form of catalyst is described in numerous patents including U.S. Pat. Nos. 1,628,190, 2,384,501; 3,627,790, and 3,809,658. Briefly, this type catalyst is formed by the chemical leaching of an intermetallic compound formed between a catalytically active metal and a less noble metal. The leaching preferentially removes the less noble metal and produces a porous structure having a high surface area predominantly comprised of the catalytically active metal. The catalytically active metals include, but are not limited to the transition metals. Intermetallic compounds between such a catalytically active element and a less noble element such as Al are usually employed.
In a different subject area, but one which relates to this invention, it is known that under certain solidification conditions an oriented microstructure may be produced in eutectic composition. This is taught in U.S. Pat. Nos. 3,124,452, 3,528,808; 3,552,953; 3,554,817; 3,564,940 and 3,671,223 all of which are assigned to the assignee of the present invention.